A pneumatic conveying system is generally used to convey polymeric pellets, for example from a rail car or truck to a receiving container. When pneumatically conveying pellets, it is usually necessary to use a high transport velocity to prevent settling and to maintain movement of the pellets. Unfortunately, such a high transport velocity tends to cause frictional heat to build up as the pellets travel and contact a tube or conduit wall, and can cause melting of some of the pellets. The melted portions of the pellets can adhere to the tube or conduit wall in a thin polymeric layer, which can eventually break loose from the wall, travel with the pellets, and contaminate the process downstream. These thin strips of polymeric material, which are deposited on the walls of the tube or conduit by the moving pellets, are considered contaminants and are referred to by various names such as streamers, snakeskin, angel hair, etc.
Accordingly, a need exists for a method and apparatus that efficiently removes streamers from a flow of pellets.